Why are English days named what they are?

Charlotte Guest
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Reading time: 4 minutes

Ever wondered why Monday is called Monday or how Wednesday got its name? The names of the days of the week in English have fascinating origins, rooted in ancient history and steeped in mythology. Understanding these origins not only enriches our language ability but also provides intriguing insights into cultural heritage.

Origins of the days of the weeks names
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Origins of the seven-day week

The concept of a seven-day week has ancient origins, tracing back to the Babylonians around 1500 BCE. The Babylonians, keen astronomers, divided their lunar cycle into four weeks of seven days each, aligning with the phases of the moon. This practice was later adopted by the ancient Greeks and Romans, who found the seven-day cycle practical and meaningful.

The ancient Hebrews' influence also played a crucial role in establishing the seven-day week. According to the biblical account of creation, God created the world in six days and rested on the seventh, establishing a divine precedent for a seven-day cycle. This tradition was deeply ingrained in Hebrew culture and religious practices.

By the 1st century CE, the Romans had formalized the seven-day week, integrating it into their calendar system. This structure, combining astronomical observations and religious traditions, eventually spread throughout the Roman Empire and beyond, becoming the foundation of the modern seven-day week we use today.

In the Arabic and Hebrew calendars, the day begins at sunset, which contrasts with the Swahili concept of the day starting at sunrise and the Western world, where the day starts at midnight. This highlights the cultural influences on how days are numbered and identified within these different calendrical systems.

Origins of days of the week

How did Monday get its name? Meaning of Monday

Monday is named after the Moon. The Old English word for Monday was Monandæg, which translates to "Moon's day". This naming convention is quite common across various languages; for instance, in Latin, it's dies Lunae, also meaning "day of the Moon".  

Tuesday name origin

Tuesday is named after the Norse god Tiw (also known as Tyr), a god of war and sky. The Old English term Tiwesdæg directly reflects this association. The connection to Mars, the Roman god of war, can also be seen in other languages, such as French (mardi).

Why is Wednesday called Wednesday?

Wednesday is named after Odin (or Woden), the chief god in Norse mythology. The Old English Wodnesdæg translates to "Woden's day". This day is associated with Mercury in Roman mythology, which is why it's called miércoles in Spanish and mercredi in French.

Thursday name meaning

Thursday is named in honor of Thor, the Norse god of thunder. The term 'Thor's day' serves as the etymological basis for Thursday. In Old English, it was Þūnresdæg (Thunor’s day). The link to Jupiter, the Roman king of gods and god of thunder, explains the name jeudi in French and jueves in Spanish.

Friday history and meaning

Friday is named after Frigg (also known as Frigga or Freya), the Norse goddess associated with love and beauty. The Old English term Frigedæg means "Frigg's day". In Roman mythology, this day is linked to Venus, the goddess of love, which is reflected in names like viernes in Spanish and vendredi in French.

Saturday name origin

Saturday is unique among the English day names as it retains its Roman origin, specifically named after the Roman god Saturn, the Roman god of wealth and time. The Old English Sæternesdæg directly references this deity. Interestingly, in other Germanic languages, the name often refers to the Sabbath, such as Samstag in German.

Sunday - The sun's day

Sunday is named after the Sun. Icelandic uniquely retains 'only the Sun' as the name for Sunday, rejecting names derived from pagan gods. The Old English Sunnandæg translates to “Sun’s day”, reflecting its importance and reverence in various cultures. This name is consistent across many languages, highlighting the widespread significance of the Sun.

The importance of understanding day names etymology

Understanding the etymology of day names helps language learners grasp the historical context and deepens their appreciation of English. These names are more than just labels for days; they are windows into ancient beliefs, cultures and linguistic evolution. The influence of Greek and Latin names on the naming of the days of the week during the Greco-Roman tradition is particularly notable, as the classical planets from Hellenistic astrology played a significant role in this process.

Exploring the origins of the day names in English reveals a blend of mythology, history and language evolution. From the Moon to Norse gods to Roman deities, each name tells a story of cultural significance.

Read our blog posts 'Fantasy, the English language and Tolkien'.

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